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在预试验基础上,选用50只清洁级昆明小鼠随机分为5组,每组10只。紫锥菊提取物经口服灌药的剂量分别为2500、1250、625 mg/kg,另设环磷酰胺阳性对照组与0.9%生理盐水阴性对照组。于第二次给药后24 h处死小鼠,取胸骨脊髓做切片,在油镜下观察微核,计算微核率。试验结果表明,紫锥菊提取物对小鼠骨髓细胞的微核率无影响,结果为阴性。  相似文献   
3.
杨斌  代飞燕  金卫华 《猪业科学》2004,21(12):56-58
将自然感染MG的土杂鸡,随机分为7组,1、2、3组分别为病毒I号,按每kg体重0.25ml、0.50ml、1.00ml给药,4、5、6组分别为泰乐星,按每kg体重50mg、100mg、200mg给药,2次/d,连续7d,7组为空白对照。投药后,进行临床症状及气囊病理评分、MG血清抗体检测和疗效试验。结果显示:病毒I号与泰乐星在缓解临床症状、减少气囊炎病变率、降低气囊病变程度和死亡率等方面两者均无显著差异(P>0.05),而试验组与对照组差异显著(P<0.05)。说明病毒I号与泰乐星达到同样的治疗效果。  相似文献   
4.
对健康昆明小鼠连续一周灌服不同浓度的紫锥菊根末生药液,观察其对健康昆明小鼠中枢神经系统、呼吸系统和心率的影响,以考察紫锥菊根末的潜在不良反应.结果表明,紫锥菊根末对健康昆明小鼠的中枢神经系统、呼吸系统和心率均无明显影响.  相似文献   
5.
经确诊30日龄患腹水综合症的艾维茵肉鸡100只,随机分为2组;另选50只30日龄健康肉鸡为Ⅲ组,作正常对照。I组为喂中药组,Ⅱ组、Ⅲ组为未喂中药组。喂药后第5d,I组的肝干湿比值与Ⅱ组相比有极显著差异性(P<0.01);右心重量(RV)、右心重量与全心重量比(RV/TV)、心肺干湿比值比Ⅱ组低,有显著差异性(P<0.05);与Ⅲ组相比,差异不显著(P>0.05)。试验表明,本方剂能够缓解机体组织的瘀血水肿,改善机体血液循环障碍。  相似文献   
6.
中药渣及添加剂对幼兔增重效果的研究   总被引:5,自引:0,他引:5  
本试验利用药厂生产“增长乐”取汁后的中药渣,配合于家兔日粮中并对其生长效果进行观察研究。在小白鼠预试的基础上,添加3%的中药渣并配合200ppm铜、75ppm喹乙醇,200ppm铜+0.3克四环素于幼兔日粮中。结果表明;添加3%中药渣较对照组提高日增重9.6%,节料7%;配合使用200ppm铜,则效果更佳。总的结果表明:中药渣及添加剂作为一种促生长剂增加到家兔日粮中是可行的  相似文献   
7.
牛冷冻精液稀释液中草药配方的初步研究   总被引:3,自引:0,他引:3  
通过比较以淫羊藿为主要成分的单方及复方中草药提取液对牛冷冻精液解冻后精子活率、畸形率、顶体完整率及低温保存时间的影响,以期开发牛冷冻精液中式稀释液。将三种不同配方的淫羊藿提取液分别以6.25%、12.5%、25.0%、50.0%的体积分数添加于稀释液中,制作牛颗粒冻精,利用干解冻法(40~42℃)解冻后分别检查精子活率、畸形率和顶体完整率,评定其品质。结果表明:配方三取得了较佳的冷冻效果。其提取液添加12.5%时精子冻后活率平均达到0.56,极显著高于其他各组(P〈0.01):精子顶体完整率最高达到76.80%。畸形率仅14.61%,低温保存时间长迭138h。配方三最有利于生产牛冷冻精液。  相似文献   
8.
 Nitrous oxide (N2O) emissions and methane (CH4) consumption were quantified following cultivation of two contrasting 4-year-old pastures. A clover sward was ploughed (to 150–200 mm depth) while a mixed herb ley sward was either ploughed (to 150–200 mm depth) or rotovated (to 50 mm depth). Cumulative N2O emissions were significantly greater following ploughing of the clover sward, with 4.01 kg N2O-N ha–1 being emitted in a 48-day period. Emissions following ploughing and rotovating of the ley sward were much less and were not statistically different from each other, with 0.26 and 0.17 kg N2O-N ha–1 being measured, respectively, over a 55-day period. The large difference in cumulative N2O between the clover and ley sites is presumably due to the initially higher soil NO3 content, greater water filled pore space and lower soil pH at the clover site. Results from a denitrification enzyme assay conducted on soils from both sites showed a strong negative relationship (r=–0.82) between soil pH and the N2O:(N2O+N2) ratio. It is suggested that further research is required to determine if control of soil pH may provide a relatively cheap mitigation option for N2O emissions from these soils. There were no significant differences in CH4 oxidation rates due to sward type or form of cultivation. Received: 1 November 1998  相似文献   
9.
本研究利用Illumina高通量测序技术对PP333处理的朱顶红进行了RNA-seq测序,共获得26.91 Gb的数据,对其进行过滤去冗余后得到Unigene 106 684个,总长度为92 002 803 bp,平均长度为862 bp,N50为1 494 bp,GC含量为42.47%,Q20均达98%以上,表明测序质...  相似文献   
10.
Shelterwood seed cutting in conjunction with herbicide site preparation has proven effective at regenerating Allegheny hardwood forests, but the long-term impact of this silvicultural system on herbaceous vegetation has not been determined. From 1994 to 2004, we studied the impacts of operational herbicide site preparation using glyphosate plus sulfometuron methyl herbicides in the context of a shelterwood seed cut. Our study took place on 10 partially cut sites on the Allegheny National Forest in northwestern Pennsylvania. Half of each site received herbicide and half did not in a split-plot design with repeated measures. Fences were erected after year six because deer impact had increased. Resilience of individual species and the community were determined using measures of percent cover by species or species groups and indices of diversity and similarity comparing post-treatment to pre-treatment conditions and controls. In the short term, abundance of all species was reduced and there were four fewer species on average in treated areas. No species was eliminated by herbicide across all sites in the long term. Graminoids were more abundant on treated plots after year six. Targeted ferns remained less abundant on treated than control plots after 10 years. Species richness recovered within 4 years following treatment. Shannon Diversity and Shannon Evenness were greater in treated than in control plots over the full study period, but the differences were not significant in any single year. The richness-based Jaccard index of similarity did not differ between control and treatment plots after year two, while relative abundance influenced indices showed significant differences through year eight. Results suggest that herbaceous layer vegetation is resilient to the disturbance created by herbicide-shelterwood treatments.  相似文献   
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